过硫酸铵消化-砷铈催化分光光度法测定尿碘不确定度评定

[目的]对过硫酸铵消化-砷铈催化分光光度法测定尿碘的不确定度进行评定。[方法]通过分析测定过程,识别不确定度来源,量化不确定度分量,计算合成不确定度和扩展不确定度。[结果]用本方法测定尿碘的扩展不确定度为0.035C。有必要在结果计算中应用校正因子。[结论]为提高测定结果的准确性,减小不确定度,建议在检测过程中采取一些技术改进措施。     

检测水发或水产品中甲醛的快速定性检测试纸的实验研究与应用

[目的]研究快速有效地鉴定水产品、水发制品是否人为添加甲醛的方法。[方法]2003年,研制水产品或水发产品中甲醛的定性快速检测试纸,进行试纸检测灵敏度和抗干扰分析,并与我国卫生部在2001年推荐的乙酰丙酮分光光度法同时进行样品检测。[结果]试纸检测甲醛下限1×10-3mol/L(30×10-6kg/L);试纸检测甲醛时间不超过3min;试纸检测甲醛具有抗干扰性。[结论]本发明试纸已于2005年取得中国发明专利(专利号:ZL 03 1 78350.3)。     

密闭微波辅助提取细梗胡枝子不同药用部位中黄酮类化合物

本文建立了微波提取细梗胡枝子不同药用部位中黄酮类化合物,并以分光光度法测定其含量的实验方法。在微波单因素提取的基础上,采取L9(34)正交设计优化实验,优化了萃取乙醇浓度、液固比、微波功率和微波辐射时间等提取条件,确定了微波辅助萃取法提取细梗胡枝子样品中叶、枝和根等不同药用部位中的黄酮类化合物的最佳工艺参数分别为:叶:微波功率40%(340W),乙醇浓度为50%,液固比为80 ml/g,提取时间6 min;枝:微波功率40%(340W),乙醇浓度为50%,液固比为80 ml/g,提取时间5 min;根:微波功率50%(425W),乙醇浓度为60%,液固比为90 ml/g,提取时间5 min。在最优条件下测得黄酮类化合物含量分别为:10.43%(叶),5.91%(枝),(根)5.29%。在上述最优条件下进行了重复性和加样回收率实验,与索氏提取法、超声波提取法以及乙醇冷浸法比较,微波辅助萃取法具有操作简便、快速、重现性好等特点。     

可见光及紫外光分光光度法测定丁香总黄酮含量的研究

目的研究可见光及紫外分光光度法测定丁香总黄酮含量的方法。方法可见光分光光度法是以芦丁为参照品,硝酸铝作显色剂,在510 nm波长测定总黄酮含量。紫外分光光度法是以芦丁为参照品,在359 nm波长测定总黄酮含量。结果可见光法平均回收率是99.46%,紫外光法是99.13%。RSD分别是1.15%和0.90%。结论紫外分光光度法是一种较理想的测定方法。     

A rapid colorimetric method for the determination of Losartan potassium in bulk and in synthetic mixture for solid dosage form

Two new rapid reproducible and economical spectrophotometric methods are described for the determination of Losartan potassium in bulk and in synthetic mixture for solid dosage forms. Both methods are based on the formation of an orange-red and orange ion-pair complex due to the action of Calmagite (CT) and Orange-II (O-II) on Losartan potassium in acidic medium (pH 1.2). Under optimised conditions, they show an absorption maxima at 491 nm (CT) and 486 nm (O-II), with molar absorptivities of 1.74×10³ and 1.75×10³ l mol⁻¹ cm⁻¹ and Sandell's sensitivities of 0.2649 and 0.2637 per 0.001 absorbance unit for CT and O-II, respectively. The colour is stable for 5 min after extraction. In both cases Beer's law is obeyed between 10 and 100 μg ml⁻¹. The proposed method was successfully extended to synthetic mixture for solid dosage forms.     

Titrimetric and spectrophotometric assay of some antihistamines through the determination of the chloride of their hydrochlorides

Two simple, rapid and reliable methods for the determination of four antihistamines based on the measurement of the chloride of their hydrochlorides are described. In the titrimetric method, the chloride content of each drug is determined by titrating with mercury(II) nitrate using diphenylcarbazone-bromothymol blue as indicator. In the spectrophotometric method, to a fixed concentration of mercury(II)-diphenylcarbazone complex different amounts of drug are added and the decrease in absorbance of mercury(II)-diphenylcarbazone complex, consequent to the replacement of diphenylcarbazone of the complex by the chloride of the drug, was measured at 540 nm. The stoichiometry of the reaction that forms the basis for titrimetry is assessed. Different variables affecting the color formation in spectrophotometry were studied and optimized. At the wavelength of maximum absorption, Beer's law is obeyed in the 0-100 microg ml(-1) range. The molar absorptivity and Sandell sensitivity are calculated. The proposed methods were applied for the analysis of pharmaceutical formulations containing these drugs. Statistical treatment of the experimental results indicates that the procedures are precise and accurate. Excipients used as additives in pharmaceutical formulations did not interfere in the proposed procedures as shown by the recovery studies.     

作业场所空气中锡的微波消解-氢化物发生原子荧光光度测定法

目的 建立作业场所空气中锡的微波消解-原子荧光光度测定法.方法 将采样完毕的微孔滤膜按微波消解程序处理后,将消解液进一步处理,以原子荧光光度法测定锡.结果 方法的线性范围为0.3～100.0μg/L,检出限为0.3μg/L,最低检出浓度为0.000 1 mg/m3(以采集75 L空气样品计),测定相对标准偏差为2.7%～3.5%,样品加标回收率为96.5%～104.7%.结论 该方法具有快速准确、灵敏度高、精密度好等优点,可用于作业场所空气中锡的测定.     

催化光度法测定体液腺苷脱氨酶的活性

目的：改进了测定体液中腺苷脱氨酶活性的催化光度测定法。方法：利用Berthelot显色反应，通过测定单位时间内释放出来的NH，量来推算ADA的活性，并通过正交设计与单因素试验相结合优化测定条件，得到最佳测定方法。结果：批内和批间相对标准偏差范围分别为1．16％-2．17％，2．49％～3．25％。与文献方法对比，试剂用量减少一半，反应时间缩短40min。结论：本试验操作快速简便，灵敏度高，重复性好，用于测定。ADA活性较低的体液也能获得满意结果。可在临床推广应用。     

溴甲酚绿法测定血清白蛋白条件研究

目的利用分光光度法对溴甲酚绿法测定血清．白蛋白的条件进行了研究，结果在pH3．7Britton-Robinson（B-R）缓冲液中，溴甲酚绿（BCG）与血清白蛋白能形成稳定的绿色复合物；BCG-血清白蛋白复合物的最大吸收波长631nm比溴甲酚绿445nm本身红移，吸光度与白蛋白的含量在最大吸收波长下呈线性关系；白蛋白浓度在0-0．5g／L范围内符合Beer定律，该方法选择性高、重复性好、测定含量范围宽，操作简单，测定结果与双缩脲法相吻合。     

分光光度法测定黄根片中铝的含量

目的该文采用铝试剂—分光光度法测定黄根片中铝的含量。方法在醋酸-醋酸铵缓冲系(pH 6.2)中,铝-铝试剂生成红色配合物,在25℃,最大吸收波长为510 nm处测吸光度。结果此法线性范围0.004~0.032 mg/m l,r=0.998 5,平均回收率为96.97%,RSD为0.70%(n=5)。结论用该方法可测量中药中铝的含量,方法简便,灵敏度和准确度较高,结果满意。